Double-heading air-brake system.



F.'H. DUKESMITH. I DOUBLE HEADING AIR BRAKE SYSTEM.

APPLICATION nun NOV.16, 1912. 7

1,102,020; Patented June 30, 1914.

3 SHEETS-SHEET l.

P. H. DUKESMITH.

DOUBLE HBADING AIR BRAKE SYSTEM.

APPLIGATION FILED NOV. 16, 1912,

Patented June 30,191 L 3 SHEETS-SHEET 2.

F. H. DUKBSMITH.

DOUBLE HEADING AIR BRAKE SYSTEM.

APPLIOATION FILED NOV. 16,1912.

1,102,020, Patented June 30, 1914- 3 SHEETSSHEET 3.

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COLUMBIA PLANODRAPH (10.. WASHINGTON, D. 5.

UNITED STATES PATENT OFFICE.

FRANK H. DUKESMITH, OF MEADVILL'E, PENNSYLVANIA, ASSIGNOR TO THOMAS C. VAN HOB/NE, OF PITTSBURGH, PENNSYLVANIA.

DOUBLE-READING- AIR-BRAKE SYSTEM.

Specification of Letters Patent.

Patented June 30, 1914:.

Application filed November 16, 1912. Serial No. 731,826.

SMITH, a resident of Meadville, in the county of Crawford and State of Pennsylvania, have invented a new and useful Improvement in Double-Heading Air-Brake Systems, of which the following is a specification.

This invention relates to what is known as a double heading valve device to be applied to air brake equipment upon locomotives and for the purpose of automatically controlling the supply of air from the main reservoir to the train pipe on each locomotive.

Then two or more locomotives are coupled together, as occurs in double heading, the brakes are usually under the control of the engineer on the first locomotive. On the following locomotives the main reservoirs and engineers brake valves are usually cut out by turning the cut-out cocks in the train pipes below the brake valves, or by placing the engineers brake valves in lap position with all ports closed. This arrangement, of course, places the control of the brakes for the entire train entirely in the hands of the engineer of the first locomotive, but the result is that the burden of supplying the entire system with air is thrown entirely upon the pump on the first locomotive, the system receiving no assistance from the pumps on the following 1000- motive or locomotives due to the cutting off of their main reservoirs from the train pipe.

It has heretofore been proposed to provide a suitable bypass around the cut-out cocks and the train pipes on the following locomotives, which by-pass is controlled by a normally open valve device, which will be operated by an increase of train pipe pressure, as when releasing the brakes, to open the bypass so that in release and running positions the train pipe may be supplied from the main reservoirs and pumpsof the following locomotives, and which valve device on a decrease of train pipe pressure, as occurs when the brakes are being applied by the engineers valve on the first locomotive, closes said lay-pass. In actual practice, it

has been found difficult to secure the closing of these valve devices at the time of applying the brakes, for the reason that said valve devices are operated entirely by unba-lancing of pressures on opposite sides of the piston, A

which pressures are supplied from the train pipe or equivalent source, and as said valve devices are normally open, the train pipe is being fed from the main reservoirs of the following locomotives about as rapidly as it is being evacuated at the first locomotive.

Consequently, the train pipe pressure does not reduce sufficiently to actuate this valve device to close the by-pass or to secure the application of the brakes.

My invention is designed to overcome the foregoing difficulties and to provide means whereby such normally open valve device is positively closed whenever the engineers brake valve on the first locomotive is brought to either service or emergency application positions; or in other words, by actuating such valve device by means not dependent upon variations in train pipe pressure. This object may be accomplished in various ways, as by mechanical connections between the engineers brake valve on the first locomotive and the cut-out valve devices on the following locomotive or locomotives, but preferably by fluid pressure means controlled by the engineers valve on the first locomotive and arranged to admit pressure from some source independent of the train pipe to a piston which actuates the cut-out valve on the following locomotive or locomotives.

In the accompanying drawings, Figure 1 is a diagrammatic view of an air brake equipment for a locomotive supplied with my invention, this being for the first locomotive of a multiple header; Fig. 2 is a similar view showing the equipment for the second or following locomotive in a multiple header; Fig. 3 is a plan view partly in section showing the engineers brake valve and cut-out valve; and Fig. 4 is a view partly in elevation and partly in vertical section through the engineers brake valve and supplemental valve actuated thereby.

In each of Figs. 1 and 2 the reference numeral 1 indicates the main reservoir, 2 the loo engineers brake valve, 3 the train pipe, 4

which are found in all modern air brake equipments for locomotives.

11 shows a small equalizing reservoir ortank for supplying the pressure for the equalizing piston oi modern lVestinghouse air brake valves. The equipment shown is a standard West-nigh ouse equipment and has been selected for illustrative purposes only, as my invention applies to any automatic air brake system.

In carrying out my invention, I place in the train pipe below the engineers brake 'alve a cut-out valve device 14, shown in detail in Fig. 3. This valve device may be of any suitable form and is so arranged that norm ally or in running position of the engineers bra-kevalve it remains open. For this purpose its valve 15 is provlded with a groove 16 which when it is in alinement with the train pipe sections, maintains the train pipe normally open, while when the body portion 15 brought across the train pipe the latter is closed. This valve is held normally open by means of train pipe pressure entering through a passage 17 on the engineers valve side of the device underneath the piston 18. A spring 19 is arranged to move the valve to close the train pipe connection. This spring, however, is not suiticiently strong to close the valve against train pipe pressure underneath the piston 18. F or instance, if train pipe pressure is pounds, this springwill exert thirty pounds pressure.

The chamber 20 behind the piston 18 is connected by pipe 21 to a suitable source of air supply independent of the train pipe, and said pipe 21 is controlled by the engineers brake valve of the first engine. As shown, the independent source of air supply is a small reservoir 23, which is shown as supplied from the equalizing reservoir 1.1 through check controlled passage 23*, although it may be supplied directly from the main reservoir. The pipe 21 is provided with a cut-oil valve 24 which is controlled by the engineers brake valve. As illustrated in Figs. and 4t this cut-oll valve is shown as a slide valve 25 having a groove 26 which when brought into alinement with the pipe section 21 opens communication from the reservoir 23 to the chamber 20 behind the piston 18. A spring 27 is provided for normally moving the valve 25 to close the pipe 21.. The valve is provided with a stem 28 projecting through one head of the casing and adapted to be actuated by the engineers brake valve handle, such as providing the latter with a cam 29 to bear against the end of said stem. This cam 29 is of such shape and size that when the engineers brake valve is in either service or emergency application position, it bears against the stem 28 to push the valve over suficiently to bring the groove 26 into alinement with the pipe sections 21, whereas when the brake valve is in any other position, namely, release, running or lap, the cam does not contact with the stem 28, thereby enabling the spring 27 to hold the valve 25 closed. The slide valve 25 also controls an exhaust port 30 which is closed when groove 26 registers with pipe 21 and is open when groove 26 is out of alinement with pipe 21. Each locomotive is provided with this equipment, and in prac tice the pipes 21 are provided with ordinary coupling members, so that when the locomotives are coupled together, the valve 24; on the leading locomotive controls the cut-ofi valve 14 on the following locomotive.

The operation is as follows: When the handle of the engineers brake valve on the leading locomotive is in either release, running or lap positions, the cam 29 does not contact with the stem 28. Consequently, the valve 24 closes the communication between the reservoir 23 and valve 14 and at the same time the chamber 20 is open to the atmosphere at the valve 24 through the release port 30. Consequently, the piston 18 is opposed on one side by the spring 19 and on its opposite side by train pipe pressure, which latter overbalances the spring and moves the valve 14 to open position. This is the normal position of this valve during running, and consequently the engineers brake valve on the following locomotive can be placed in running position and the train pipe pressure maintained in part by the mam reservoir and pump on the second locomotive, thereby relieving the pump on the first locomotive. TV hen, however, the brakes are applied, the engineers brake valve on the first locomotive is turned to either service or emergency positions in both of which the cam 29 pushes the stem 28 inwzn'dly, thereby moving the valve 25 to close exhaust port 30 and bring the groove 26 into alinement with the two pipe sections 21. Fluid pressure from the small reservoir 23 is thereby admitted behind the piston 18. This pressure will be at least as high as train pipe pressure and consequently the train pipe pressure underneath the piston 18 is overbalanced by the combined action of the fluid pressure and spring 19 behind the piston. This moves the valve lt to close the train pipe, thereby preventing the main reservoir of the second locomotive feeding into the train pipe while the engineefls brake valve on the first locomotive is evacuating said pipe. The result is that the train pipe pres sure is quickly reduced and the brakes applied in the usual way. I

By operating the cut-oil valve 14: by a source of fluid pressure independent of train pipe pressure, the difliculties with prior equipments are entirely overcome, and the valve is positively closed whenever the engineers brake valve on the leading locomotive is brought to brake application position.

While I prefer to use fluid pressure for actuating the cut-off valve, it is obvious that this valve may be controlled from the engineers brake valve on the leading locomotive, either by mechanical means or by electrical means, and I intend by the terms of the claims herein made, to cover all such modifications.

What I claim is:

1. In an automatic air brake, the combination of a main reservoir, a train pipe, a normally open valve device controlling communication from the main reservoir to the train pipe, and a valve actuated by an engineers valve on an adjacent engine and arranged to admit pressure to said valve device to close the same When the engineers brake valve is in brake application position.

2. In an automatic air brake, the combination of a main reservoir, a train pipe, a normally open valve device controlling communication from the main reservoir to the train pipe, and means controlled directly from an engineers valve on an adjacent engine for closing said valve device When the engineers valve is in position to reduce train pipe pressure and to permit the opening of said valve device When the engineers valve is in position to increase train pipe pressure.

3. In an automatic air brake, the combination of a main reservoir, a train pipe, a normally open valve device controlling communication from the main reservoir to the train pipe, means actuated by train pipe pressure for holding said valve device normally open, and means actuated by an engineers valve on an adjacent engine When in position to reduce train pipe pressure to close said valve device.

4:. In an automatic air brake, the combination of a main reservoir, a train pipe, a normally open valve device controlling communication from the main reservoir to the train pipe, and means controlled from an engineers valve on an adjacent engine for admitting to the valve device to close the same a pressure from a source independent of the train pipe.

5. In an automatic air brake, the combination of a main reservoir, a train pipe, a normally open valve device controlling communication from the main reservoir to the train pipe, and a supplemental valve arranged to be opened by movement of an engineers valve and arranged When open to admit pressure to said valve device to close the latter.

6. In an automatic air brake system, the combination of a main reservoir, a train pipe, a valve device controlling communication from the main reservoir to the train pipe, fluid pressure actuated means for operating said valve device, and a supplemental valve actuated by an engineers valve for admitting pressure to said fluid pressure means.

7. In an automatic air brake, the combination of a main reservoir, a train pipe, a valve device controlling communication from the main reservoir to the train pipe, a movable abutment for actuating said valve, and a supplemental valve controlling communication to said movable abutment, said supplemental valve being arranged to be actuated by an engineers valve and being connected to a source of fluid pressure, to the atmosphere and to said movable abutment.

In testimony whereof, I have hereunto set my hand.

FRANK H. DUKESMITH.

\Vitnesses:

\VILLIAM B. WVHAn'roN, WM. P. LARKIN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, I). 0. 

